Okan Gülbahar
Ege University
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Annals of Allergy Asthma & Immunology | 2005
Okan Gülbahar; Gunseli Ozturk; Nihat Erdem; Ali Can Kazandi; Ali Kokuludag
BACKGROUND More than 250 cases of allergic contact dermatitis due to propolis have been described. A few of these occurred in beekeepers. OBJECTIVE To describe a case of psoriasiform dermatitis caused by propolis in a beekeeper who thought that his lesions were related to honeybee stings. METHODS A 45-year-old beekeeper experienced hand dermatitis for the past 5 years. He believed that the lesions occurred and worsened when he was stung by honeybees. He was prescribed topical corticosteroids several times, but because he was stung frequently, the drugs never helped control the lesions. In the past few years, he frequently had contact with propolis during honey collection, but he denied the role of propolis because he was wearing gloves while handling the beehives. For diagnostic evaluation, skin biopsy, skin prick tests (SPTs), identification of specific IgE antibodies, and atopic patch tests were performed. RESULTS Skin biopsy showed psoriasiform contact dermatitis. Results of SPTs to honeybee and serum specific IgE for Apis mellifera remained negative. Results of the atopic patch test performed using A mellifera SPT material were also negative in the first 20 minutes and on the second and third days. However, propolis showed a positive erythematopapular reaction on day 2. The patient never again worked as a beekeeper, and neither did he, as far as he knew, use any medical or cosmetic products that contained propolis. His hand lesions improved almost completely. CONCLUSION Dermatitis due to propolis should never be disregarded in beekeepers, and every effort should be put forth to make a correct diagnosis and to convince the patients of the cause.
Annals of Allergy Asthma & Immunology | 2003
Okan Gülbahar; Aytül Zerrin Sin; Nihal Mete; Ali Kokuludag; Cengiz Kirmaz; Filiz Sebik
BACKGROUND Cats represent one of the most important sources of indoor allergens. The sensitization rate can reach up to 60% in western countries. Keeping cats indoors is uncommon in big cities in Turkey, but cats living in the streets are common. OBJECTIVE To investigate the prevalence of sensitization to cats in patients with respiratory allergy from Izmir, Turkey, and its relationship to home cat allergen levels. METHODS A total of 387 patients (70.8% female; mean age, 34.3 years) with respiratory allergic diseases (rhinitis and/or asthma) were included in this study. Skin prick test to cat was performed. House dust samples were collected from the living room of 25 patients and 14 healthy subjects. The major cat allergen (Fel d 1) levels were measured by Dustscreen. Fel d 1 levels given by the manufacturer were as follows: 0.05, 0.13, 0.40, 1.1, and 6.2 mU/mL. RESULTS The prevalence of cat sensitivity was 44.7% (n = 173). Only 6 patients (1.6%) had a history of feeding a cat in their houses. Thirty-six (92%) of 39 houses had detectable levels of cat allergen (mean Fel d 1 level, 2.24 +/- 2.69 mU/mL). The mean Fel d 1 levels were 1.58 +/- 2.51 mU/mL in the healthy group, 1.91 +/- 2.61 mU/mL in the asthmatic group, and 3.26 +/- 2.85 mU/mL in the group with allergic rhinitis (P = 0.12). The prevalence of cat sensitivity in patients who had 1.1 mU/mL of Fel d 1 in their homes was 57.1%. This rate was five times lower (11.1%) in patients who had the highest Fel d 1 level (6.2 mU/mL) in their homes. CONCLUSIONS The prevalence of cat sensitivity in Izmir, where cats are generally not kept within homes, is as high as in western countries. The sampled houses have measurable levels of Fel d 1 even in the absence of indoor cats. High prevalence of cat sensitivity in Izmir is probably due to indirect exposure.
Annals of Allergy Asthma & Immunology | 2004
Nihal Mete; Aytül Zerrin Sin; Okan Gülbahar; Münevver Erdinç; Filiz Sebik; Ali Kokuludag
BACKGROUND Patients with allergic rhinitis and bronchial hyperresponsiveness (BHR) may be at higher risk of developing asthma. OBJECTIVE To investigate whether reactivity to aeroallergens in skin prick testing (SPT) and serum eosinophil cationic protein levels can be used to predict BHR in allergic rhinitis patients. METHODS Fifty-nine consecutive patients with allergic rhinitis underwent SPTs using grass, tree, weed, parietaria, Alternaria, Aspergillus, mites, and cat and dog dander extracts. Methacholine challenge tests were performed using spirometry. RESULTS Methacholine-induced BHR was detected in 23 patients (39%). Of 59 patients, 14 had 1 positive SPT response, 35 had 2 to 4 positive responses, and 10 had more than 4 positive responses. There was a significant inverse correlation between methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20) and the number of positive SPT responses (r = -0.28; P = .03). The BHR-positive patients had a mean of 4 positive SPT responses, whereas BHR-negative patients had a mean of 2.6 (P = .04). Nine BHR-positive patients (39%) and only 1 BHR-negative patient (3%) had more than 4 positive SPT responses (P < .001). There was no correlation between serum eosinophil cationic protein levels and methacholine PC20 doses. There was a strong association between hyperresponsiveness to methacholine and both cat and dog dander sensitivity (P < .001 and P = .001, respectively). CONCLUSIONS Allergic rhinitis patients with SPT responses to a higher number of allergens are more likely to have BHR. Whether the number of positive SPT responses correlates with the risk of developing asthma in allergic rhinitis patients remains to be determined.
International Archives of Allergy and Immunology | 2012
Nihal Mete Gökmen; Ramazan Ersoy; Okan Gülbahar; Ömür Ardeniz; Aytül Zerrin Sin; Mehmet Ünsel; Ali Kokuludag
Background: It has previously been demonstrated that subcutaneous immunotherapy with allergoids positively affects clinical and immunological parameters even after 7 preseasonal injections. However, its effect on basophil activation remains unclear. We investigated the effect of preseasonal allergoid immunotherapy on basophils and concomitantly assessed its clinical and immunological efficacy in olive pollen-monosensitized patients. Methods: This study enrolled 437 consecutive patients with respiratory allergy and positive skin prick tests (SPTs); 212 (48.5%) patients were sensitized to olive pollen, and 33 (7.5%) patients were sensitized to olive pollen only. Of these patients, 23 received preseasonal immunotherapy with an olive pollen allergoid. The olive pollen-specific basophil activation, the titrated nasal provocation test, the nasal symptom score, and olive pollen-specific IgE, IgG1 and IgG4 levels were evaluated before immunotherapy and 8 months after the end of immunotherapy in the follow-up visit. Results: In comparison to baseline evaluation, 7 preseasonal injections of an allergoid resulted in a significant decrease in the percentage of basophils expressing CD63 (29 vs. 7%, respectively, p < 0.0001) and a significant increase in the titrated nasal provocative dose (1/10 vs. 1/1, respectively, p < 0.01). SPT induration diameters caused by an olive pollen extract decreased (12 mm at baseline vs. 5.5 mm at follow-up, p < 0.005), as did nasal symptom score (7 at baseline vs. 3 at follow-up, p < 0.01). Olive pollen-specific IgE (17.5 vs. 50 kU/l, p < 0.012), IgG1 (0.16 vs. 2.9 µg/ml, p < 0.0001) and IgG4 (0.07 vs. 1.92 µg/ml, p < 0.0001) levels significantly increased. Conclusions: Immunotherapy with 7 preseasonal injections of an olive pollen allergoid decreases olive pollen-specific basophil activation over 8 months, an effect observed in vitro and in vivo.
Annals of Allergy Asthma & Immunology | 2005
Ömür Ardeniz; Okan Gülbahar; Nihal Mete; Candan Çiçek; Ozen K. Basoglu; Aytül Zerrin Sin; Ali Kokuludag
BACKGROUND Arthritis is an important and sometimes life-threatening complication in patients with common variable immunodeficiency (CVID). OBJECTIVE To describe a patient with CVID and arthritis due to Chlamydia pneumoniae, which is usually regarded as a respiratory tract pathogen and has not previously been detected in the synovial fluid by cell culture technique. METHODS Routine bacteriologic, virologic, mycologic, and tuberculosis cultures were performed. The patients synovial fluid was examined for fastidious organisms that might be causative pathogens of arthritis, such as chlamydiae, and special cell culture methods were used. Serologic tests were performed to determine viral and bacteriologic etiology. RESULTS The patient had a history of recurrent respiratory tract infections, and the latest exacerbation was followed by arthritis. Cytologic examination of the fluid yielded abundant lymphocytes. Chlamydia pneumoniae was detected in synovial fluid specimens by cell culture technique. Her nasopharyngeal swab and sputum culture specimens were also positive for this pathogen. She was diagnosed as having arthritis caused by C pneumoniae and was given antibiotherapy. CONCLUSION Chlamydia pneumoniae should be kept in mind as a causative pathogen in patients with CVID and arthritis, especially when effusion fluid is full of lymphocytes rather than polymorphonuclear cells and no organism is grown on routine cultures.
Allergy | 2004
Okan Gülbahar; Nihal Mete; Ali Kokuludag; Aytül Zerrin Sin; Filiz Sebik
Exposure to house dust mites (HDMs) is a major risk factor for allergic sensitization and asthma (1). Assessing HDM allergen exposure at home is critical to evaluate risk factors for sensitization and can play a role in controlling environmental factors that contribute to asthma severity (2). Although it is reported that the predominated HDM was Dermatophagoides pteronyssinus in Turkish homes (3), data on mite allergen levels has never been reported. Therefore, we aimed to investigate HDM allergen levels of homes in Izmir, the third populated city in Turkey situated next to Aegean Sea and to identify predictors of dust mite allergen concentration. Dust samples were obtained from 25 homes of allergic patients with perennial symptoms, consecutively referred to our out patient clinic for the first time for their allergies. Fourteen healthy subjects served as a control group. House dust samples were collected from an area of 1 m with a 1200-W, filtered vacuum cleaner. Dust mite allergen (Der p 1 and Der f 1) concentration was determined by Dustscreen assay, a method easier to perform and as satisfactory as enzyme-linked immunosorbent assay (4). The HDM allergen levels were expressed as lg/m. The minimum detection level of Der p 1 and Der f 1 was 0.1 lg/m. Independent predictors of allergen concentration were assessed. Either Der p 1 or Der f 1 was detected in 21 of 39 homes (53.8%). Dermatophagoides pteronyssinus predominated in most of the houses (71.4%). Twentythree percent of houses were coinhabited by D. farinae and D. pteronyssinus. Der p 1 was detected in twenty houses in the range of 0.4–5.4 lg/m (median 2). We observed Der p 1 >2 lg/m of dust in 55% of the houses. Whereas Der f 1 was detected in only six houses (median 1, range 0.1–6.4 lg/m). Der p 1 levels were significantly higher in allergic subjects houses than healthy controls (median 2 vs 0.4 lg/m, P 1⁄4 0.041). Twenty-one of 25 allergic subjects (84%) were sensitive at least to D. farinae or D. pteronyssinus assessed by skin prick test. Independent predictors of higher levels were evidence of moisture, such as mildew or water stains in the home and residency at seaside. In conclusion, more than half of the houses in Izmir had detectable levels of dust mite allergen. Dermatophagoides pteronyssinus was the most frequently found species. Allergic patients encountered more HDM allergens than normal subjects in their home, and this situation may emphasize the importance of environmental factors in the development of allergic diseases. Indoor moisture and residency at seaside were predictors of higher mite allergens.
International Archives of Allergy and Immunology | 2011
Belgin Kesim; Zehra Oya Uyguner; Asli Gelincik; Nihal Mete Gökmen; Aytül Zerrin Sin; Gül Karakaya; Füsun Erdenen; Ömür Ardeniz; Ferhan Özşeker; Okan Gülbahar; Bahattin Çolakoğlu; Suna Büyüköztürk
Background: No published data presently exist concerning hereditary angioedema (HAE) in Turkey. The aim of the study was to initiate a preliminary multicentric evaluation about HAE and to determine the genetic properties of Turkish patients. Methods: Based on records drawn from four medical centers we identified a total of 70 subjects, belonging to 60 unrelated families, fulfilling clinical and laboratory criteria for diagnosis of HAE with C1 inhibitor deficiency. Ten type I patients, and their first-degree relatives, underwent genetic analysis for HAE. Results: The majority of patients were female (60%), the mean age was 37.7 ± 14.1 years. The mean age at the time of first angioedema symptom was 12.5 ± 9.2 years. Mean time lag between first symptom and diagnosis was 26 ± 14.4 years. All but 3 subjects had HAE type I. Family history of angioedema was present in 75.7% of the cases. Cutaneous swelling was reported by 87.1% of the patients, facial edema by 65%, abdominal symptoms by 74.3% and approximately one half (55.7%) had experienced one or more laryngeal attack. Genetic analysis of 10 families demonstrated that 5 carried a mutation that had never been previously described. Conclusion: We found that the clinical features of Turkish HAE patients were consistent with previously described patterns of this rare disease. The most noteworthy feature identified in the study was a significantly long duration between the first symptom appearance and final diagnosis. Our detection of different mutations in 10 patients confirms the allelic heterogeneity of the disease.
International Archives of Allergy and Immunology | 2012
Mehmet Ünsel; Nihal Mete; Ömür Ardeniz; Aytül Zerrin Sin; Okan Gülbahar; Ali Kokuludag
Background: The precision of the methods used to diagnose latex allergy is of great importance due to false-positive results. Neither the skin prick test (SPT) nor the latex-specific IgE assay has 100% diagnostic accuracy. We analysed the diagnostic value of latex-specific IgE by the first-ever concomitant use of the SPT and nasal provocation test (NPT). Methods: Twenty-seven latex-sensitive patients (group 1), 46 aeroallergen-sensitive patients (group 2a) and 33 healthy subjects (group 2b) participated in the study. All groups underwent an SPT with latex and aeroallergens and an NPT with latex. Latex-specific IgE and total IgE levels were measured by the ImmunoCAP assay. Results: Latex-specific IgE was positive in 92.6, 30.4 and 9.1% of groups 1, 2a and 2b, respectively. The 11 aeroallergen-sensitive patients in group 1 and all of the patients in group 2a were predominantly sensitised to pollens (grass, weed and tree) and reacted to a lesser degree to house dust mite, moulds and animal dander. Combined pollinosis was remarkably more prevalent in patients with positive latex-specific IgE in group 2a than in those with negative latex-specific IgE (p = 0.001). The NPT was positive in 84.6% of group 1 and negative in all control subjects. The sensitivity, specificity, negative predictive value and positive predictive value of the latex-specific IgE assay were 90.9, 72.2, 96.3 and 50%, respectively. Conclusion: The high rate of false-positive results for latex-specific IgE by ImmunoCAP should be taken into account when making a diagnosis of latex allergy in patients with pollinosis, especially in those sensitised to more than one pollen species.
Allergy | 2009
M. Ünsel; Nihal Mete; Ömür Ardeniz; S. Göksel; Ramazan Ersoy; Aytül Zerrin Sin; Okan Gülbahar; Ali Kokuludag
Background: Most studies regarding natural rubber latex (NRL) allergy have concentrated on the prevalance using skin prick test (SPT) and specific IgE assay. The objective of this study is to examine the target organ (skin, nasal mucosa) responses in patients with positive SPT to NRL using the nasal provacation test (NPT) and glove use test (GUT).
International Archives of Allergy and Immunology | 2008
Ömür Ardeniz; Cigir Biray Avci; Aytül Zerrin Sin; Gökhan Özgen; Fulya Gunsar; Nihal Mete; Okan Gülbahar; Ali Kokuludag
Background: Common variable immunodeficiency (CVID) is characterized by hypogammaglobulinemia and a defect in antibody production. Herein we describe 3 patients diagnosed with CVID in whom vitamin D deficiency was detected in the absence of enteropathy. Methods: Biochemical and immunological analysis, serum osteocalcin, parathyroid hormone, 25-OH vitamin D, 1,25(OH)2 vitamin D, vitamin A, vitamin E, urinary calcium, and deoxypyridinoline measurements were carried out. Vitamin D receptor (VDR) expression was examined in the peripheral blood mononuclear cells and hair follicles by reverse transcriptase polymerase chain reaction. VDR gene polymorphism was evaluated by high-performance liquid chromatography. Results: None of the patients presented nutrient deficiencies other than vitamin D. Two of them were free of osteomalacia-related symptoms. VDR expression was found to be lower in the peripheral blood mononuclear cells and hair follicles when compared to the control group. Conclusions: Patients with CVID may present asymptomatic vitamin D deficiency. Vitamin D and VDRs play an important role in the innate immune system and modulate Toll-like receptor-related responses. Delay in diagnosis may predispose these patients not only to irreparable bone loss but also to infections, and autoimmune and malignant disorders, thus emphasizing the importance of prompt intervention.